Chassis for motor vehicles



April 28, 1931- N. L. CAUSAN 1,803,055

CHASS IS FOR MOTOR VEHICLES Filed April 18, 1929 2 Sheets-Sheet l April28, 1931. N. CAUS AN 1,803,055

CHASSIS FOR MOTOR VEHICLES Filed April '18. 1929 2 Sheets-Sheet 2 Fig.4.

Arm/m Patented Apr. 28, 1931 UNITED "STATES PATENT, OFFICE,

N EMORIN LAURENT CAUSAN, OF SUBESNES, FRANCE cir-Assls FOR MOTORVEHICLES Application filed April 18, 1929, Serial No. 856,284, and inFrance April 25,1928.

The present invention has for its object a chassis or frame for motorvehicles which will be free from any twisting stresses regardless ofconditions of ground unevenness and load distribution.

In the accompanying drawings, several different embodiments of theinvention are illustrated, by way of example, all of which are based onthe same general principles.

Figure 1 isa diagrammatic plan view of the preferred form, utilizingconventional front and rear axles;

Fig. 1 is a horizontal section showing the mounting of the tubularcross-ties, and Fig. 1 is a detail of one of the ball-and-socket jointsindicated in Fig. 1, while Fig. 1 is a diagrammatic section on line ZZ,Fig. 1;

Figs. 2 and 3 are, respectively, a side elevation and a plan view of amodification;

Figs. 4 and 5 are corresponding views of a second modification, andFigs. 6 and 7 are slmilar views of a third modification.

Referring first to Fig. 1 and its related F igures 1 1 and 1, it will beseen that the frame or chassis proper consists of-two side rails 1connected by two tubular cross-ties 2, 2', upon each of which ties arepivotally mounted two levers; those for tie 2 being designated 3, 3b,and those for tie 2 being designated 3c and 3a. The outer ends of thelevers are connected'to the corresponding axles 18 by ball-and-socketjoints 4, 4b, 40, 4a, one of these joints being illustrated in Fig. 1

Each side rail 1, as shown in Fig. 1', has fastened to it a conical partor member 12 rig 1dly secured to the adjacent end of a stretcher rod 13that passes through the tubular crosstie 2 or 2', said rod bein designed'to insure the rigidity of the assem lage by means of a o clampingdevice 14 which is accessible from the outside.

The aforesaid levers are mounted on the ends of the cross-ties wherethey are held in place by shoulders 15, and they are provided at 16'and16 with ears throughwhich are formed square holes 17 to receive one endof one of the suspension springs 5, the other end of, which is securedto the opposite side rail by means of a suitable socket member 17'.

Fig. 1 shows only one lever and only one spring; the other lever beingmounted symmetrically with the one represented, while the two springsare arranged in different horizontal planes (see Fig. 1). to preventthem from interfering with each other. The

said springs are preferably in the form ofstraight rods working undertorsion. 1

The condition essential to neutralizin the torsional stresses set up bythe poor distribution of the loads upon the wheels 19, is that thejoints 4, 4b, 40 and 4a (viewed in plan) be arranged on the extensionsof the imaginary bias lines a-b and c-d (Fig. 1) which connect thecenters 7 and 10 of'the portions of the two side rails located betweenthe two cross-ties 2, 2 with the centers 8 and 9 of said ties.

To demonstrate that with such an arrangement the non-warpabilit of thechassis is obtained independently o the rigidity of its component parts,it will be supposed thatthe chassis is supported solely by the twojoints 4 and 4a. The assemblage of. the parts 3, 2 and5 and the portionof the side raihl comprised between the points 6 and 7 may be consideredas a lever whose working points are 4, 8 and 7, so that the chassissustains,at

each of the points 8 and 9 (the centers of the 1 two cross-ties 2, 2'),a force'acting upwardly from bottom to top, and at each of the points 7and 10 (the centers of the two side 1 rails) a force acting downwardlyfrom top to bottom.

Supposing, now, that the chassis is supported by the other two joints4?) and 4c alone, it will readily be understood that the forces applied,respectively, at the points 7, 8, 9- and 10 will not change. The chassissustaining the same forces applied at the same points,

with the rear part of the modified structure shown in Figs. 2 and 3wherein, in order to reduce the length of the levers carried by thecross-ties, the frame constituted by said 5 ties andthe two side rails1v is widened and is independent of the frame 11 which supports thevehicle body. The additional modifications shown, on the one hand, inFigs. 4 and 5, and in Figs. 6 and 7, on the other hand, difl'er,respectively,

from the corresponding constructions represented in Fig. 1 and in Figs.2-3 merely in that the levers 3 and 3 carry the wheels 19 directly, themounting being the same as that in known vehicles with independentwheels, The main frame in Figs. 6 and 7 is designated 1 and thebody-supporting frame is designated 11', to agree with'Figs. 2, 3. Figs.-6 and 7 further agree with Figs. 2, 3 inthat the condition that thecenters of the wheels (when seen in plan) must be situated onprolongations of the imaginary bias lines connectin the said wheelcenters with the mid-' dle pomts of theside rails and the cross-ties,for the purpose of neutralizing torsional stresses, is fully answered.therein, but is only approximately answered in Figs. 4, 5.

I claim as my invention 1. A chassis for motor vehicles which is inherently non-warpable regardless of distribution of the load upon thewheels, such chassis comprising two side rails; two cross-tiesconnecting the corresponding front and rear portions of said! rails; apair of levers piv-- oted on each cross-tie; a suspension springassociated with each lever and working under torsion, eachspringconnecting one end of the corresponding lever with the opposite siderail; and a pivotal connection between the other end of each lever andthe adjacent wheel axle; the points of said pivotal connec tions beingsituated, when viewed in plan, in prolongations of the imaginary lineswhich ]0l11 the middle parts of the'portions of-the side rails locatedbetween the cross-ties with the middle parts of said ties.

2. A chassis for motor vehicles which is in herently non-warpableregardless of the distrlbution of the load upon the wheels, such chasslscomprising two side rails and two cross-tles connected together; a pairof supporting levers pivoted on each cross-tie; a suspension springassociated with each lever and working under torsion; and a set ofwheels, one for each lever, eachlever being plvotally connected at oneend with a wheel, and at the other end, by means of the assoelatedspring, with the opposite side rail; the pivot point of each wheel beingsituated 1n the prolongation of animagina line wlnchoins the middle partof a si e rail wlth that of a cross tie.

In testimony whereof I aflix my signature.

65 NEMORIN LAURENT CAUSAN.

